Metodología para la desagregación detallada del Lcoe de plantas fotovoltaicas a gran escala

RESUMEN: Este artículo presenta una metodología para evaluar los costos nivelados de la electricidad (Levelized Cost of Electricity) LCOE , en plantas fotovoltaicas (Photovoltaic - PV) a gran escala. Para ello se propone una desagregación detallada de los LCOE a partir de una taxonomía rigurosa que evalúa los Costos de Inversión (Investment Cost - IC )y los Gastos de Operación (Operation and Maintenance – O&M). Partiendo de la estructura de la Administración de Información Energética (Energy Information Administration – EIA) que desglosa los IC en cinco componentes, hemos añadido un nivel adicional de desagregación denominado elementos. Asimismo, una nueva estructura para desagregar los costos de O&M es presentada. La metodología es evaluada en plantas PV de 20 MW y 150 MW PV hipotéticamente ubicadas en el municipio de Uribia (Guajira Colombia). También se desarrolla un análisis de sensibilidad determinístico usando factores como el Costo Promedio Ponderado de Capital (WACC – Weighted Average Capital Cost), la energía producida, los gastos de O&M y los IC con el ánimo de facilitar las decisiones de los inversionistas.ABSTRACT: This paper presents a breakdown cost methodology to evaluate Levelized Costs of Electricity for large-scale Photovoltaic (PV) plants. The breakdown is based on a comprehensive taxonomy to evaluate Investment Costs (IC) and Operation and Maintenance (O&M) expenditures. We added an IC disaggregation level, called elements, on top of the five-component breakdown of the Energy Information Administration (EIA). In addition, a novel structure for disaggregating O&M costs is also proposed. The methodology is evaluated over a 20-MW and a 150-MW PV power plant hypothetically placed in the municipality of Uribia (Guajira Colombia). Also deterministic sensitivity analysis based on discount rate (WACC, Weighted Average Capital Cost), energy generated, O&M costs and IC is performed to aid investors in their decision

Magnetic Field Sensors Based on Giant Magnetoresistance (GMR) Technology: Applications in Electrical Current Sensing

The 2007 Nobel Prize in Physics can be understood as a global recognition to the rapid development of the Giant Magnetoresistance (GMR), from both the physics and engineering points of view. Behind the utilization of GMR structures as read heads for massive storage magnetic hard disks, important applications as solid state magnetic sensors have emerged. Low cost, compatibility with standard CMOS technologies and high sensitivity are common advantages of these sensors. This way, they have been successfully applied in a lot different environments. In this work, we are trying to collect the Spanish contributions to the progress of the research related to the GMR based sensors covering, among other subjects, the applications, the sensor design, the modelling and the electronic interfaces, focusing on electrical current sensing applications

Análisis externo de factores determinantes de competitividad: sector salud en Boyacá, utilizando el diamante de Porter

Con este artículo, se logró realizar una caracterización externa del sector salud en el departamento de Boyacá, utilizando la herramienta del diamante de Porter; con el fin de analizar el entorno competitivo de la región, con el cual se integran e interactúan cuatro elementos: condiciones de la demanda, factores de producción o servicio, sectores conexos y de apoyo, estrategia, estructura y rivalidad de la empresa, que determinan la formación y competitividad de los agrupamientos de sectores conectados para poder lograr el éxito del sector de la salud, o de las empresas que están en este renglón de la economía, para lo cual se contó con información documental y entrevistas realizadas a gerentes de empresas del sector salud; una de las conclusiones es que el problema del sector salud no es financiero, ya que existen recursos en el sistema, pero que desafortunadamente las malas prácticas como la corrupción y demora en los pagos a las IPS por parte de las Entidades Promotoras de Salud; dejan evidenciar que el problema radica en una inadecuada gestión financiera, que está impactando en la calidad de la prestación del servicio y la competitividad del sector.AbstractIt was possible to make an external characterization of the health sector in the department of Boyacá. The Porter’s diamond was used to analyze the competitive environment of the Region. Four elements are integrated and interacted: conditions of the demand; factors of production or service; related and support sectors; strategy, structure and competition of the company. These determine the competitiveness of the connection of sector cluster to be able to be successful in the health sector or the Companies which are in this row of economy. For this, the documental information and interviews done to managers  of Companies of the health sector was important. One of the conclusions is that the Health sector has not got any financial problem because there are resources in the system, but corruption and delays in payments from the side of Health Promotion Organization is something that has to be taken into account. It means that there is an inappropriate finance management which  effects dramatically the quality assurance service.

Acrometástasis en miembro inferior por adenocarcinoma pulmonar

ResumenSe presenta el caso de un paciente que refiere un cuadro de dolor en el miembro inferior izquierdo, más acusado en zona pretibial, atraumático, desde hace 6 meses. El dolor, de características no mecánicas, era refractario al tratamiento, constante, impidiendo el descanso nocturno. Se realizaron estudios complementarios cuyo primer diagnóstico fue osteomielitis, iniciándose tratamiento antibiótico. Al no ceder el cuadro, fue evaluado nuevamente con el diagnostico final de acrometástasis en el miembro inferior izquierdo como primer signo clínico de un adenocarcinoma pulmonar.Acrometástasis en miembro inferior secundaria a un caso de adenocarcinoma pulmonar es infrecuente y suele proceder de cáncer colorrectal y/o tracto urogenital. En ocasiones puede inducir a una sospecha diagnostica errónea, con el consiguiente retraso en el diagnóstico.AbstractThe case is presented of a patient who referred to a clinical history of non-traumatic pain, of six months onset, in the left lower limb, which was more intensive in pretibial region. The pain was non-mechanical in character, treatment resistant, constant, and with night rest difficulty. Several tests were performed, with osteomyelitis being the primary diagnosis, and antibiotics were started. There was no improvement, and the patient was evaluated again, with the final diagnosis of left lower limb acrometastasis as the first clinical sign of lung adenocarcinoma.Acrometastasis in lower limbs due to lung adenocarcinoma is uncommon and usually arises from colorectal or urogenital cancer. Occasionally it may be lead to an erroneous suspicion resulting in a delay in diagnosis

A Non-Invasive Thermal Drift Compensation Technique Applied to a Spin-Valve Magnetoresistive Current Sensor

A compensation method for the sensitivity drift of a magnetoresistive (MR) Wheatstone bridge current sensor is proposed. The technique was carried out by placing a ruthenium temperature sensor and the MR sensor to be compensated inside a generalized impedance converter circuit (GIC). No internal modification of the sensor bridge arms is required so that the circuit is capable of compensating practical industrial sensors. The method is based on the temperature modulation of the current supplied to the bridge, which improves previous solutions based on constant current compensation. Experimental results are shown using a microfabricated spin-valve MR current sensor. The temperature compensation has been solved in the interval from 0 °C to 70 °C measuring currents from −10 A to +10 A

Multiple particle tracking analysis in isolated nuclei reveals the mechanical phenotype of leukemia cells.

The nucleus is fundamentally composed by lamina and nuclear membranes that enclose the chromatin, nucleoskeletal components and suspending nucleoplasm. The functional connections of this network integrate external stimuli into cell signals, including physical forces to mechanical responses of the nucleus. Canonically, the morphological characteristics of the nucleus, as shape and size, have served for pathologists to stratify and diagnose cancer patients; however, novel biophysical techniques must exploit physical parameters to improve cancer diagnosis. By using multiple particle tracking (MPT) technique on chromatin granules, we designed a SURF (Speeded Up Robust Features)-based algorithm to study the mechanical properties of isolated nuclei and in living cells. We have determined the apparent shear stiffness, viscosity and optical density of the nucleus, and how the chromatin structure influences on these biophysical values. Moreover, we used our MPT-SURF analysis to study the apparent mechanical properties of isolated nuclei from patients of acute lymphoblastic leukemia. We found that leukemia cells exhibited mechanical differences compared to normal lymphocytes. Interestingly, isolated nuclei from high-risk leukemia cells showed increased viscosity than their counterparts from normal lymphocytes, whilst nuclei from relapsed-patient's cells presented higher density than those from normal lymphocytes or standard- and high-risk leukemia cells. Taken together, here we presented how MPT-SURF analysis of nuclear chromatin granules defines nuclear mechanical phenotypic features, which might be clinically relevant.post-print1994 K

Scaling-up climate services with users in Latin America

Latin America farmers are highly vulnerable to climate variability, with crop losses observed throughout the region on a virtually annual basis. For instance, as indicated by the United Nations’ Food and Agriculture Organization (FAO) and World Food Program (WFP), the 2014–2017 drought conditions in Central America affected over 3.5 million people in Guatemala, Honduras and El Salvador. At the same time, local stakeholders and farmers generally have limited access to existing climate and forecast information, do not have sufficient capacities to understand the climate information and/or mechanisms to relate this information to the impact that climate variations can generate at a local level. This precludes the translation of information into actionable knowledge, and therefore into action. In this study, we describe a process through which scientists and strategic partners have co-developed, tested and scaled out an approach to assess, co-produce, translate and transfer climate information to enable agricultural decision making –the Local Technical Agroclimatic Committees (LTAC). LTACs allow open and clear dialogues about climate variations at multiple timescales, how these can affect crops, and the design of measures to reduce crop loss, particularly providing agronomic recommendations to farmers. We systematically describe the process of evidence generation, creation, partner engagement, scaling up, and monitoring of the approach throughout Latin America. Currently, 35 LTACs exist in 9 Latin American countries, engaging more than 250 public and private institutions, increasing the resilience and food security of an estimated 330,000 farmers, and potentially transforming how Latin American farmers manage climate risk. The study illustrates changes in institutional and farmers' capacities to co-produce, translate and use climate information and explores how better climate and crop prediction models can effectively underpin this process. We show how strategic alliances with farmer organizations, national public, and private and regional climate outlook forums help deliver improved and accurate climate information to users. Finally, we document how LTACs and their integration with other local-scale processes have led to changes in farmers’ management practices to take better advantage of good climatic conditions or avoid losses

Estudio exploratorio de los espacios de práctica autónoma de la producción oral de los estudiantes de la Licenciatura en Lenguas Modernas de la Pontificia Universidad Javeriana

Se ha observado que, en el programa de Licenciatura en Lenguas Modernas de la Pontificia Universidad Javeriana, se presentaban deficiencias en la producción oral de algunos estudiantes a pesar que la Licenciatura comprende un horario de clases exhaustivo de inglés, además de unas horas autónomas en las cuales el estudiante debe practicar o reforzar lo visto en clase. Partiendo de este problema, esta investigación tiene como objetivos explorar de qué manera practican los estudiantes de la Licenciatura en Lenguas Modernas la producción oral en inglés en su trabajo autónomo, teniendo en cuenta los cinco aspectos establecidos por el Marco Común de Referencia Europeo para las Lenguas (MCREL) (Council ofEurope, 2001). Además, identificar qué motiva a los estudiantes a practicar la producción oral autónomamente. Teniendo en cuenta el objetivo mencionado anteriormente, esta investigación es tanto cuantitativa como cualitativa, con un diseño no experimental transaccional, de carácter exploratorio descriptivo. Para la obtención de datos se aplicaron dos encuestas, en la cual la segunda se basaba en una escala de Likert. Éstas permitieron conocer los espacios que los estudiantes estaban utilizando, así como lo que se estaba haciendo en cada uno de estos. Finalmente, a partir del análisis e interpretación de los datos arrojados por las encuestas, se identificaron 10 espacios de producción oral. Se observó que los espacios que más usan los estudiantes son los que no involucran una producción como tal, sino mas bien, algunos aspectos de esta habilidad como la pronunciación, entonación y vocabulario. Además, en cuanto a la motivación al practicar estos espacios, se descubrió que, los estudiantes practican autónomamente para mejorar su nivel de lengua en general.It has been observed that, in the program of Degree in Modern Languages of the Javeriana University, therewere deficiencies in the oral production of some students despite the fact that the Degree comprises a comprehensive English class schedule, and autonomous hours in which the student must practice or reinforce what he has seen at the classroom. According to this problem, this research aims to explore how students in a bachelor´s in Modern Languages practice the oral production in English in their autonomous hours, taking into account the five aspects established by the Common European Reference Framework for Languages (MCREL) (Council of Europe, 2001). Besides, it aims to identify what motivates students to practice oral production autonomously. Taking into account the objectives mentioned above, this research is both quantitative and qualitative, with a design non-experimental and transactional, exploratory descriptive. For data collection two surveys were applied, in which the second was based on a Likert scale. These allowed the researchers to know the spaces that the students were using, and what was being done in each one of those. Finally, from the analysis and interpretation of the data obtained from the surveys, there were identified 10 spaces of oral production. It was observed that the most used spaces for the students werethose that did not involve a production, but rather, some aspects of this ability as pronunciation, intonation and vocabulary. Moreover, as for the motivation to practice these spaces, it was found that students practiced independently in order to improve their level of language in general.Licenciado (a) en Lenguas ModernasPregrad

Optimal Power Dispatch of Distributed Generators in Direct Current Networks Using a Master–Slave Methodology that Combines the Salp Swarm Algorithm and the Successive Approximation Method

This paper addresses the Optimal Power Flow (OPF) problem in Direct Current (DC) networks by considering the integration of Distributed Generators (DGs). In order to model said problem, this study employs a mathematical formulation that has, as the objective function, the reduction in power losses associated with energy transport and that considers the set of constraints that compose DC networks in an environment of distributed generation. To solve this mathematical formulation, a master–slave methodology that combines the Salp Swarm Algorithm (SSA) and the Successive Approximations (SA) method was used here. The effectiveness, repeatability, and robustness of the proposed solution methodology was validated using two test systems (the 21- and 69-node systems), five other optimization methods reported in the specialized literature, and three different penetration levels of distributed generation: 20%, 40%, and 60% of the power provided by the slack node in the test systems in an environment with no DGs (base case). All simulations were executed 100 times for each solution methodology in the different test scenarios. The purpose of this was to evaluate the repeatability of the solutions provided by each technique by analyzing their minimum and average power losses and required processing times. The results show that the proposed solution methodology achieved the best trade-off between (minimum and average) power loss reduction and processing time for networks of any size

Capital Intelectual, valoración mediante modelación

Los procesos acelerados de cambio en las organizaciones, a partir de tecnologías de la información y las comunicaciones y por acercamientos a los mercados mundiales, dan lugar al concepto de sociedad de la información y el conocimiento, lo que se convierte en un factor de creación de valor, facilitando ventajas competitivas de las empresas y generando productos, servicios e ideas nuevas. Lo anterior ha permitido comprender la aparición de la gestión del conocimiento en los ámbitos de las actividades empresariales y organizacionales, y la generación de conocimiento alrededor de la investigación y de la innovación. El fin principal de la gestión del conocimiento se ubica en el valor agregado del conocimiento organizacional, lo que posibilita un desarrollo adecuado del capital intelectual. La evidencia de este desarrollo se hace con modelos de valoración del capital intelectual, ubicados en un marco meramente cualitativo, sin herramientas adecuadas para un seguimiento riguroso y con utilización de programas informáticos. En ese sentido cabe la pregunta: ¿es posible disponer de un modelo matemático para hacer valoración de capital intelectual, hacerle seguimiento y permitir retroalimentación a la misma organización?. Por tales razones es necesario disponer de estrategias que posibiliten la modelación del capital intelectual, como forma de enriquecer el conocimiento empresarial y de diseñar instrumentos adecuados para su valoración. Dentro de las modelaciones obtenibles aparecen los modelos lineales y matriciales, a partir de la configuración de los datos de los componentes del capital intelectual. Se presenta entonces un modelo de valoración de capital intelectual a partir de una simulación